Former prime minister Tony Blair has taken a swipe at UKIP, saying beneath the facade lurks something "pretty nasty and unpleasant".

Mr Blair said it was time to "confront and expose" reactionary forces like Nigel Farage's party and the National Front in France.

He said they did not have any "actual solution to the problem of the 21st century".

And he cautioned Labour leader Ed Miliband not to try to pursue an anti-immigration agenda to stave off the threat from UKIP, saying it would only confuse voters.

Mr Blair said Britain could only yield power and influence in the world through alliances and the collective bargaining power of Europe.

In an interview on BBC Radio 4's Today programme, the former Labour leader praised the beleaguered Nick Clegg for his "courage" and "leadership".

Ed Miliband has also been criticised over Labour's election performance

Mr Blair said: "We are confronted by what I think are these very reactionary forces. We have to confront them, expose them and take them on ... you have got to take on and expose the fact these parties have no actual solutions to the problem of the 21st century."

He said the rationale for being a part of Europe was power and added: "For a country like Britain, if you want to exercise weight and power and influence, you have got to do it through alliances and the obvious alliance for us is the one literally on our doorstep."

He said: "For the Labour Party, if it decides to follow UKIP either on its anti-Europe platform or even worse, frankly, on its anti-immigration platform, then all that will happen is that it will confuse its own supporters and it won't actually draw any greater support."

Mr Blair added he did not think supporting the EU was the deciding factor in the Liberal Democrats' poor performance.

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"The problem they have is nothing to do with Europe. The problem they have is very simple. They fought the 2010 election on a platform significantly to the left of Labour and then ended up in a Conservative Government with a platform significantly to the right of Labour ... there's not really a cure for that," he said.